Optimal Rebalancing of Binary Search Trees
نویسنده
چکیده
We give, for any reasonable function f, a scheme for rebalancing a binary search tree with amortized O(f(n)) work per update while guaranteeing a height bounded by dlog(n+1)+1=f(n)e for all n. As a corollary, in the semi-dynamic case, height dlog(n+1)e can be guaranteed with amortized O(log n) work per insertion. Both results match existing lower bounds, and hence provide an exact characterization of the amortized cost of rebalancing a binary search tree.
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